A study done on mice at the University of Tokyo supports this idea. The researchers found that a certain type of cells called beige fat can actively break down fat and sugar to improve insulin sensitivity and increase metabolism. Beige fat was also found to help regulate energy balance.
Where do these fat cells come from? Exposure to cold for long periods of time can “stress” the body into turning the bad fat that most people have into good fat. Researchers in the study of mice at the University of Tokyo found that long-term cold exposure can actually stress the white fat cells into developing more mitochondria and eventually becoming more efficient, calorie-burning beige cells. One group of mice was kept at 39 degrees Fahrenheit and another at 86 degrees Fahrenheit for one week. Without any change in diet, the mice that were kept at the lower temperature had more thermogenic activity -- meaning their cells were able to burn calories and stored fat to create heat.
Shivering creates body heat short-term by warming up the muscles. In a long-term process called thermogenesis, brown fat cells create heat to keep the body warm. When you are cold for a long enough time, the white fat cells are forced to start acting like brown fat. This protein, JMJD1A becomes altered to JMJD1A and this white cells becomes a beige cell, which is thermogenic.
Studies show that to make a difference in the fat cells the temperature has to be in the non-shivering zone, which has been found by some to be around 40 degrees Fahrenheit. Becoming too cold can be dangerous and cause hypothermia and even cardiac arrest so it’s important for us to continue to further research this concept.
If more research confirms the findings of this study, maybe this could become a new fitness craze. We will have to play it cool and see.